Extreme weather patterns experienced over the holiday period are predicted to continue as El Nino and La Nina patterns become more dominate over the country.

Flooding in the Bay of Plenty caught many people out with road closures in the area over the holiday period.

Flooding at the bottom of 17^th Avenue on New Year's Day.

Two people in the Whakatane area had to be rescued from their vehicle after they attempted to cross a flooded road on New Year's Day.

The University of Auckland's lead researcher from its School of Environment Science, Dr Anthony Fowler, says as the world continues to warm, New Zealand is likely to experience the impacts of El Nino and La Nino events.

'This means we should anticipate more extreme events, such as flooding and droughts in the regions affected by these weather patterns.”

In New Zealand, El Nino events usually bring more cool south-westerly winds.

The whole country tends to be relatively cool with associated droughts in sheltered eastern areas of both islands.

The winds reverse with La Ninas.

Moisture laden air from the subtropics elevates temperatures, especially in the North Island, and brings higher rainfall to much of the country, sometimes with associated floods.

'The El Nino / La Nina phenomenon has been referred to as the heartbeat of the world,” says Anthony.

'After the seasonal cycle and monsoons, it's the most important source of year-on-year climate variation.

'Strong events often cause incredible damage and affect hundreds of millions of people around the world, El Ninos, in particular, have been responsible for some of the devastating 20th Century droughts in Australia, floods in South America, and failure of the monsoons in India.

'To date the global climate models used to 'predict' the future have been unable to give us a clear picture of what will happen with El Nino and La Nina as the world warms,” he says.

'But understanding the phenomenon is critical to learning what climate change will mean for the world's population.”